The Millionaire(who is given no name, so I am using Cassaday's title for him in his notes) is part of the group of six people who working with Doctor Axel Brass. He was a serious man, and had an deadly obsession for justice. He was one of the group that did not have any superpowers at all.

The Millionaire is only revealed to live or work out of Chicago. All other information about him is kept hidden. His outfit for crime-fighting consists of a dark trenchcoat with a spider-like emblem on the left side of his chest, a dark brimmed hat, pistols on both sides of his waist, and a metal mask covering his nose and mouth. One strange feature about him is the fact that his entire eyes are red. Whether this is natural or perhaps contacts of some sort is never revealed.

The Millionaire died with the rest of the group, defending Earth from invaders from a parallel world.

According to Cassaday's notes The Millionaire is based off the pulp hero The Spider, a sort of predecessor to The Shadow and Batman.

"Like The Shadow, only without supernatural powers, and far, far crazier. A genius, but possessed by the need to save the world. Batman with guns and no mood stabilisers. Long leather coat, slouch hat, guns visible. A Spider design down one breast of his longcoat, in grey against the black."

-http://www.warrenellis.com/brass_people.htm

"And the dark millionaire, the man in black whose guns shouted out against crime in all its forms."

-Doctor Axel Brass, Planetary Vol. 1, All Over the World and Other Stories